1. Field of the Invention
The present invention relates to an air flow system for an internal combustion engine and more particularly, to an air swirling device having a plurality of vanes with at least one elongated slit disposed therein, respectively, which is positioned within an air cleaner of an internal combustion engine for achieving complete combustion. The air flow system is used for a spark ignition internal combustion of a carburetor type or a fuel injection type, and a diesel engine of a high compression self-ignition type.
2. Description of the Prior Art
It is known that an increase of swirl flow in a combustion chamber of an internal combustion engine improves the flame propagation speed so that complete combustion is achieved. However, there are many problems which accompany attempts at increasing air flow such as air resistance and the like. Such known facts are shown in the following prior art documents. For example, Japanese patent publication No. 59-11722 and U.S. Pat. No. 4,309,969 disclose a simple turbulence device, which includes an intake valve having a large intake resistance so that the swirling device does not create an uniform air flow. Japanese patent publication Nos. 60-17922 and 61-10645, U.S. Pat. Nos. 4,424,777, 4,432,312, and 4,539,954 disclose a device having vanes which are disposed at the vicinity of an intake valve. Such devices have various disadvantages, such as for example, air resistance, reduced inlet air into the cylinder, varying air flows of intake manifolds and strong vibrations due to different swirl ratios and volumes of intake air. U.S. Pat. Nos. 3,648,674 and 4,274,386 disclose a wire set and blades device disposed between a carburetor and a intake manifold. However, the device exhibits high friction so that the device provides a reduced amount of inlet air and is used only for a gasoline engine of the carburetor type.
In order to avoid such problems, U.S. Pat. No. 4,962,642, issued to the present inventor, discloses an air flow system for an internal combustion engine comprising an air cleaner and a swirling device disposed therein, having a plurality of vanes for causing the air to swirl thereby improving the properties of air fuel mixture and the performance of the engine. However, this air flow system, generally, has negative pressure disposed behind the plurality of vanes and air flow frictions due to the swirl of the air so that the air flow system has several disadvantages such as, for example, decrease of the intake air, lower power, and no fuel save.